Cisco wireless lan controller configuration best practices

Cisco Wireless LAN Controller (WLC) Configuration Best Practices

IntroductionMobility has rapidly changed the expectation of wireless network resources and the way users perceive it. Wireless has become the preferred option for users to access the network, and in a lot of cases the only practical one. This document offers short configuration tips that cover common best practices in a typical Wireless LAN Controller (WLC) infrastructure. The objective is to provide important notes that you can apply on most wireless network implementations.

Note Not all networks are alike. Therefore some of the tips might not be applicable on your installation. Always verify them before you perform any changes on a live network.

Prerequisites

RequirementsCisco recommends that you have knowledge of these topics:

• Knowledge of how to configure the Wireless LAN Controller (WLC) and Lightweight Access point (LAP) for basic operation

• Basic knowledge of Control And Provisioning of Wireless Access points (CAPWAP) protocol and wireless security methods

Components UsedThe information in this document is based on these software and hardware versions:

• Cisco Series WLC that runs software Release 7.6 and above.

Americas Headquarters:Cisco Systems, Inc., 170 West Tasman Drive, San Jose, CA 95134-1706 USA

Prerequisites

• Cisco 802.11n series Access points

Note Any reference to WLCs is based on software Release 7.6 and above.

The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.

2Cisco Wireless LAN Controller (WLC) Configuration Best Practices

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Best Practices

Best Practices

Network DesignThese are the best practices for network design:

Use PortFast on AP Connected Switch PortsFor APs in local mode, configure the switch port with PortFast. To configure PortFast, set the port to be connected as a "host" port (switchport host command) or directly with the portfast command. This allows a faster join process for an AP. There is no risk of loops, as the CAPWAP APs never bridges between VLANs

Interfaces Source (DHCP, SNMP, RADIUS, Multicast, and so on.)Per design, most of the CPU initiated traffic is sent from the management address in the controller. For example, SNMP traps, RADIUS authentication requests, multicast forwarding, and so on.

• The default exception to this rule is DHCP related traffic. You can also enable on each SSID "radius interface overwrite"; and then the radius for this WLAN will be sent from the dynamic interface. However, this creates design issues with Bring Your Own Device (BYOD) flow and Change of Authorization (CoA).

• Enabling radius interface overwrite on each SSID is important to take into account when you configure firewall policies, or design the network topology. It is important to avoid configuring a dynamic interface in the same sub-network as a server that has to be reachable by the controller CPU. For example, a RADIUS server, as it might cause asymmetric routing issues.

• Radius can be sourced from a dynamic interface, with the Radius override feature. This should be used only when needed by the specific topologies.

Recommended SwitchPort Modes and VLAN PruningAlways configure the switchports in "access mode" for the APs in local mode. For the switchports in trunk mode that go to the APs in FlexConnect mode (that do local switching) and to the WLCs, always prune the VLANs in order to allow only those VLANS configured on the FlexConnect AP and WLC. In addition, enter the switchport nonegotiate command on those trunks in order to disable Dynamic Trunking Protocol (DTP) on the switchport and avoid the need for the AP/WLC to process frames that are not needed as they do not support DTP. Also, resources would be wasted on the switch, which would attempt to negotiate with a device that cannot support it.

Network ConnectivityFollowing are the best practices for network connectivity:

Although most of the controller configuration is applied "on the fly", it is good idea to reload controllers after you change these configuration settings:


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– Management address

– SNMP configuration

– HTTPS encryption settings

– LAG mode (enable/disable), on this case it is mandatory

Use TAG Tagging for Management InterfaceCisco recommends to use VLAN tagging for the management interface on the WLC, as this is the only supported mode for HA scenarios. For untagged interface, the packet sent to and from the management interface assumes the Native VLAN of the trunk port to which the WLC is connected. However, if you want the management interface to be on a different VLAN, tag it to the appropriate VLAN with the command:

(Cisco Controller) >config interface vlan management <vlan-id>

Ensure that the corresponding VLAN is allowed on the switchport and tagged by the trunk (non-native vlan).

• For all trunk ports that connect to the controllers, filter out the VLANs that are not in use.

For example, in Cisco IOS® switches, if the management interface is on VLAN 20, and,VLAN 40 and VLAN 50 are used for two different WLANs, use this configuration command at the switch side:

Switch# switchport trunk allowed vlans 20,40,50

– Do not leave an interface with a 0.0.0.0 address. For example, an unconfigured service port. It might affect DHCP handling in the controller.

This is how you verify:

(Cisco Controller) >show interface summaryInterface Name Port Vlan Id IP Address Type Ap Mgr-------------------- ---- -------- --------------- ------- ------ap-manager LAG 15 192.168.15.66 Static Yes example LAG 30 0.0.0.0 Dynamic No management LAG 15 192.168.15.65 Static No service-port N/A N/A 10.48.76.65 Static No

– Do not use link aggregation (LAG) unless all ports of the controller have the same Layer 2 configuration on the switch side. For example, avoid filtering some VLANs in one port, and not the others.

– While using LAG, the traffic must arrive on the same dataplane. The controller relies on the switch for the load balancing decisions on traffic that come from the network. The controller expects that traffic that belongs to an AP always enter on the same data plane. 5500s are example of single data plane, in which traffic will always arrive on the same data plane.

– WISM2 and 8500 are WLCs with two data planes. Whenever possible, the traffic needs to arrive on the same data plane. Commonly, there is sufficient bandwidth to move frames between data planes. However, if there is limited bandwidth, the traffic may be dropped.

This is how to verify the EtherChannel load balancing mechanism:

Switch#show etherchannel load-balanceEtherChannel Load-Balancing Configuration:src-dst-ip

EtherChannel Load-Balancing Addresses Used Per-Protocol:


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Non-IP: Source XOR Destination MAC addressIPv4: Source XOR Destination IP addressIPv6: Source XOR Destination IP address

This is how to change the switch configuration (IOS):

Switch(config)#port-channel load-balance src-dst-ip

With the Cisco IOS Software Release 12.2(33)SXH6 and above, there is an option for PFC3C mode chassis to exclude VLAN in the Load-distribution. Use the port-channel load-balance src-dst-ip exclude vlan command in order to implement this feature. This feature ensures that traffic that belongs to a LAP enters on the same port.

– LAG while using VSS, or stacked switch (3750/2960) or Nexus VPC, should work as long as the fragments of an IP packet are sent to the same port. The idea is that if you go to multiple switches, the ports must belong to the same L2 "entity" with regard to load balancing decisions.

– To connect the WLC to more than one switch, you must create an AP manager for each physical port and disable LAG. This provides redundancy and scalability.

– Whenever avoidable, do not create a backup port for an AP-manager interface, even if it is allowed in older software versions. The redundancy is provided by the multiple AP-manager interfaces as mentioned earlier in this document.

Use Multicast Forwarding ModeUse multicast forwarding mode for the best performance with less bandwidth utilization. Networks with large IPV6 client counts, heavy multicast application such as Video Streaming, or Bonjour without mDNS proxy, would benefit greatly with multicast mode.

This is how to verify the multicast mode on the controller:

(Cisco Controller) >show network summary

RF-Network Name............................. rfdemoWeb Mode.................................... EnableSecure Web Mode............................. EnableSecure Web Mode Cipher-Option High.......... DisableSecure Web Mode Cipher-Option SSLv2......... DisableSecure Web Mode RC4 Cipher Preference....... DisableOCSP........................................ DisabledOCSP responder URL.......................... Secure Shell (ssh).......................... EnableTelnet...................................... EnableEthernet Multicast Forwarding............... EnableEthernet Broadcast Forwarding............... Enable

IPv4 AP Multicast/Broadcast Mode............ Multicast Address : 239.0.1.1

IGMP snooping............................... EnabledIGMP timeout................................ 60 secondsIGMP Query Interval......................... 20 secondsMLD snooping................................ Enabled

This is how to configure multicast-multicast operations on the WLC command line:

(Cisco Controller) >config network multicast mode multicast 239.0.1.1

(Cisco Controller) >config network multicast global enable


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• The multicast address is used by the controller in order to forward traffic to Access Points. It is important that the multicast address does not match another address in use on your network by other protocols. For example, if you use 224.0.0.251, it breaks mDNS used by some third party applications. Cisco recommends that the address be in the private range (239.0.0.0-239.255.255.255, which does not include 239.0.0.x and 239.128.0.x). It is also important that the multicast IP address be set to a different value on each WLC. You do not want a WLC that speaks to its Access Points to reach the APs of another WLC.

• If the Access points are on a different subnetwork than the one used on the management interface, your network infrastructure must provide multicast routing between the management interface subnet and the AP subnetwork.

Disable Internal DHCPThe controller has the ability to provide internal DHCP server. This feature is very limited and considered as convenience that is often used simple demonstration or proof-of-concept, for example in a lab environment. The best practice is NOT to use this feature in an enterprise production network.

To show if an internal DHCP server is used, this can be found in the interface configuration, where Primary DHCP server address is the same as the management IP address, an example is shown below:

(Cisco Controller) >show dhcp summary

Interface Name................................... managementMAC Address...................................... e0:2f:6d:5c:f0:40IP Address....................................... 10.10.10.2IP Netmask....................................... 255.255.255.0IP Gateway....................................... 10.10.10.1External NAT IP State............................ DisabledExternal NAT IP Address.......................... 0.0.0.0Link Local IPv6 Address.......................... fe80::e22f:6dff:fe5c:f040/64STATE ........................................... NONEPrimary IPv6 Address............................. ::/128STATE ........................................... NONEPrimary IPv6 Gateway............................. ::Secondary IPv6 Address........................... ::/128STATE ........................................... NONESecondary IPv6 Gateway........................... ::VLAN............................................. 10Quarantine-vlan.................................. 0Active Physical Port............................. 1Primary Physical Port............................ 1Backup Physical Port............................. UnconfiguredDHCP Proxy Mode.................................. GlobalPrimary DHCP Server.............................. 10.10.10.2

Change the internal DHCP server (management IP address) to a production DHCP server:

(Cisco Controller) >config interface dhcp management primary <primary-server>

A good housekeeping may also be to disable/clean up existing internal DHCP scopes; first, confirm internal DHCP scope:

(Cisco Controller) >show dhcp summary

Scope Name Enabled Address RangeScope1 Yes 10.10.10.100 -> 10.10.10.150 Either disable the scope:

(Cisco Controller) >config dhcp delete-scope <scope name>


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or

(Cisco Controller) >config dhcp disable <scope name>

SecurityFollowing are the best practices for security:

Disable Local EAPLocal EAP is an authentication method that allows users and wireless clients to be authenticated locally on the controller. Similar to internal DHCP feature, in which local EAP is also considered a convenience feature intended for simple demonstration or proof-of-concept in a lab environment. Using local EAP in an enterprise production environment is not recommended, the best practice is to disable or avoid using local EAP.

To check if a WLAN is configured to use local EAP:

(Cisco Controller) >show wlan <WLAN id>

Radius Servers Authentication................................ Global Servers Accounting.................................... Global Servers Interim Update............................. Disabled Framed IPv6 Acct AVP ...................... Prefix Dynamic Interface............................. Disabled Dynamic Interface Priority.................... wlanLocal EAP Authentication......................... DisabledRadius NAI-Realm................................. Disabled

To disable local authentication on a WLAN:

(Cisco Controller) >config wlan local-authen disable <WLAN id>

WPA2 + 802.1X WLANAlthough the controller and Access points do support WLAN with SSID using WiFi Protected Access (WPA) and WPA2 simultaneously, it is very common that some wireless client drivers cannot handle complex SSID settings. Whenever possible, Cisco recommends WPA2 only with Advanced Encryption Standard (AES). However due to standards and mandatory WiFi Alliance certification process, TKIP support is required across future software versions. Keep the security policies simple for any SSID such as a separate WLAN/SSID with WPA and Temporal Key Integrity Protocol (TKIP), and a separated one with WPA2 and Advanced Encryption Standard (AES). Since TKIP is being deprecated, Cisco recommends to use TKIP together with WEP, or migrate out of TKIP completely and use PEAP if possible.

This is how to create a WLAN with WPA2 and 802.1X enabled:

(Cisco Controller) >config wlan security wpa enable <WLAN id>

Configure RADIUS authentication server on specified WPA2/802.1X WLAN:

(Cisco Controller) >config wlan radius_server auth add <WLAN id> <Server id>

Configure RADIUS accounting server on specified WPA2/802.1X WLAN:

(Cisco Controller) >config wlan radius_server acct add <WLAN id> <Server id>


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Identity Design Tip - Use AAA OverrideIf designing for identity based networking services, where the wireless clients should be separated in several sub-networks for security reasons, such as each one with different security policies, use one or two WLANs together with the AAA-Override feature. AAA-Override feature allows you to assign per user settings. For example, move the user to either a specific dynamic interface in a separated VLAN or apply a per user Access Control List (ACL).

This is how to configure:

(Cisco Controller) >config wlan aaa-override enable <WLAN id>

Confirm WLAN configuration:


WLAN Identifier.................................. 1Profile Name..................................... WLAN-1Network Name (SSID).............................. WLAN-1Status........................................... DisabledMAC Filtering.................................... DisabledBroadcast SSID................................... EnabledAAA Policy Override.............................. EnabledNetwork Admission Control

Security

802.11 Authentication:........................ Open System FT Support.................................... Disabled Static WEP Keys............................... Disabled 802.1X........................................ Disabled Wi-Fi Protected Access (WPA/WPA2)............. Enabled WPA (SSN IE)............................... Disabled WPA2 (RSN IE).............................. Enabled TKIP Cipher............................. Disabled AES Cipher.............................. Enabled Auth Key Management 802.1x.................................. Enabled PSK..................................... Disabled CCKM.................................... Disabled.. FT-1X(802.11r).......................... Disabled FT-PSK(802.11r)......................... Disabled PMF-1X(802.11w)......................... DisabledRadius Servers Authentication................................ 10.10.10.60 1812 Accounting.................................... 10.10.10.60 1813 Interim Update............................. Disabled Framed IPv6 Acct AVP ...................... Prefix Dynamic Interface............................. Disabled

Use Faster RADIUS TimeoutIt is recommended to have the lowest configured RADIUS timeout as possible for a big or busy network. Since the longer the timeout is defined, the longer a frame re-transmission for the queue for RADIUS is held. Depending on the capacity of the network, and how busy the queue may be, a longer timeout may increase chance of retransmission failure rate. For most network deployment with high authentication count, a smaller timeout is better to improve capacity handling in the controller.


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The following example shows a default of 2 seconds that may be acceptable for a fast RADIUS fail over, but probably not enough for Extensible Authentication Protocol-Transport Layer Security (EAP-TLS) authentication. If the RADIUS server has to contact external databases (Active Directory, NAC, SQL, and so forth) then come back within the specified timeout period.

This is how to verify:

(Cisco Controller) >show radius summary

Vendor Id Backward Compatibility................. DisabledCall Station Id Case............................. lowerAcct Call Station Id Type........................ Mac AddressAuth Call Station Id Type........................ AP's Radio MAC Address:SSIDAggressive Failover.............................. EnabledKeywrap.......................................... Disabled

Authentication ServersIdx Type Server Address Port State Tout RFC3576--- ---- ---------------- ------ -------- ---- -------1 N 10.48.76.50 1812 Enabled 2 Enabled

IPSec -AuthMode/Phase1/Group/Lifetime/Auth/Encr------------------------------------------------Disabled - none/unknown/group-0/0 none/none


(Cisco Controller) >config radius auth retransmit-timeout 1 <seconds>

EAP Identity Request TimeoutIn the controllers, the default timeout for the EAP Identity request may need to increase for some situations similar to when implementing One Time Passwords (OTP) on Smart Card, where the user interaction is needed in answering the identity request. In autonomous Access points the default timeout is 30 seconds. Consider this while migrating autonomous to infrastructure wireless networks.

To show default timeouts use this command:

(Cisco Controller) >show advanced eap

EAP-Identity-Request Timeout (seconds)........... 30EAP-Identity-Request Max Retries................. 2EAP Key-Index for Dynamic WEP.................... 0EAP Max-Login Ignore Identity Response........... enableEAP-Request Timeout (seconds).................... 30EAP-Request Max Retries.......................... 2EAPOL-Key Timeout (milliseconds)................. 1000EAPOL-Key Max Retries............................ 2EAP-Broadcast Key Interval....................... 3600

This is how to change timeout (seconds):

(Cisco Controller) >config advanced eap identity-request-timeout <seconds>

EAPoL Key Timeout and Max RetriesRecommended EAPol timeout to be as small as possible for voice clients, such as IP 7920 phones. Max retries should be increased if RF environment is operating less than optimum.

(CiscoController)>showadvancedeapEAP-Identity-Request Timeout (seconds)........... 30


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EAP-Identity-Request Max Retries................. 2EAP Key-Index for Dynamic WEP.................... 0EAP Max-Login Ignore Identity Response........... enableEAP-Request Timeout (seconds).................... 30EAP-Request Max Retries.......................... 2EAPOL-Key Timeout (milliseconds)................. 1000EAPOL-Key Max Retries............................ 2EAP-Broadcast Key Interval....................... 3600

Configure EAPoL timeout:

(Cisco Controller) >config advanced eap eapol-key-timeout <milliseconds>

To configure EAPo retry counts:

(Cisco Controller) >config advanced eap eapol-key-retries <retries>

EAP Request Timeout and Max RetriesDepending on client types, some slow devices may not work with very fast times, but for the rest, it can be beneficial to have shorter timeout, and longer retry count for faster recovery on bad RF environments. This is also applicable to clients authenticating with inner EAP method such as PEAP/GTC.

To show default timeouts use this command:

(Cisco Controller) >show advanced eap

EAP-Identity-Request Timeout (seconds)........... 30EAP-Identity-Request Max Retries................. 2EAP Key-Index for Dynamic WEP.................... 0EAP Max-Login Ignore Identity Response........... enableEAP-Request Timeout (seconds).................... 30EAP-Request Max Retries.......................... 2EAPOL-Key Timeout (milliseconds)................. 1000EAPOL-Key Max Retries............................ 2EAP-Broadcast Key Interval....................... 3600

To configure EAP Request timeout:

(Cisco Controller) >config advanced eap request-timeout <seconds>

To configure EAP Request retry counts:

(Cisco Controller) >config advanced eap request-retries <retries>

CCKM Timestamp ValidationChange CCKM validation to 5 seconds to avoid pico-cells or roaming issues:

(Cisco Controller) >config wlan security wpa akm cckm timestamp-tolerance 5000 <WLAN id>

TACACS+ Management TimeoutIt is best practices to increase the retransmit timeout value for TACACS+ authentication, authorization, and accounting servers if you experience repeated re-authentication attempts or the controller falls back to the backup server when the primary server is active and reachable. This is especially true when implementing for use with One Time Password (OTP).


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(Cisco Controller) >show tacacs summary

Authentication Servers

Idx Server Address Port State Tout MgmtTout--- ---------------------- ------ ------- ----- --------1 10.10.10.60 49 Enabled 5 2

Authorization Servers

Idx Server Address Port State Tout MgmtTout--- ---------------------- ------ ------- ----- --------1 10.10.10.60 49 Enabled 5 2

To configure TACACS+ authentication retransmit timeout:

(Cisco Controller) >config tacacs auth server-timeout 1 <seconds>

To configure TACACS+ authorization retransmit timeout:

(Cisco Controller) >config tacacs athr server-timeout 1 <seconds>

Enable Infrastructure and Client Management Frame Protection (MFP)Infrastructure and client Management Frame Protection (MFP) can be used to validate all 802.11 management traffic detected between nearby Access points in the wireless infrastructure to prevent spoofing. Note enabling infrastructure MFP may generate lots of traps, and client MFP requires CCXv5 support. The evolution is to move to IEEE standard based 802.11w with support available on more recent clients such as Windows 8.

Note The interoperability between various manufacturers are being continuously updated to take advantage of CCXv5 support.

This is how to enable infrastructure MFP (globally):

(Cisco Controller) >config wps mfp infrastructure enable

This is how to enable client MFP (per WLAN):

(Cisco Controller) >config wlan mfp client enable <WLAN id>

Enable 802.11w SupportThe 802.11w standard for PMF(Protected Management Frame) is implemented since 7.4 release, which applies only to a set of robust management frames that are protected by the PMF service.

This is how to enable 802.11w (PSK enabled WLAN):

(Cisco Controller) >config wlan security wpa akm pmf psk enable <WLAN id>

This is how to enable 802.11w (802.1x enabled WLAN):

(Cisco Controller) >config wlan security wpa akm pmf 802.1x enable <WLAN id>


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Change SNMPv3 Default UserCheck on the SNMPv3 default user. By default, the controller comes with a username that should be disabled or changed.


(Cisco Controller) >show snmpv3user

SNMP v3 User Name AccessMode Authentication Encryption -------------------- ----------- -------------- ---------- default Read/Write HMAC-SHA CFB-AES


(Cisco Controller) >config snmp v3user delete default

(Cisco Controller) >config snmp v3user create nondefault rw hmacsha des authkey <encrypkey12characters>

Note Ensure that your SNMP settings must match between the controller and the Wireless Control System (WCS)/Network Control System(NCS)/Prime Infrastructure (PI). Also, you should use encryption and hash keys that match your security policies.

Enable Network Time Protocol (NTP)Network Time Protocol (NTP) is very important for several features. It is mandatory to use NTP synchronization on controllers if you use any of these features: Location, SNMPv3, Access point authentication, or MFP. The WLC will support synchronization with NTP using authentication.

This is how to enable NTP server:

(Cisco Controller) >config time ntp server 1 10.10.10.1

In order to verify, check for entries like this in your traplog:

30 Mon Jan 6 08:12:03 2014 Controller time base status - Controller is in sync with the central timebase.

This is how to enable NTP authentication:

(Cisco Controller) >config time ntp auth enable <ntp server index>

(Cisco Controller) >config time ntp key-auth add <key index>

Enable 802.11r Fast Transition802.11r is the IEEE standard for fast roaming, a concept of roaming where the initial authentication handshake with the target AP (i.e., the next AP that the client intends to connect to) is done even before the client associates to the target AP, which is called Fast Transition (FT). By default, fast transition is disabled.

Note Non 802.11r clients will not be able to connect to this wlan, make sure the clients are 802.11r capable, examples are Apple devices on version 6 and above.

This is how to enable 802.11r or Fast Transition (FT):


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(Cisco Controller) >config wlan security ft enable <WLAN id>

This is how to configure FT authentication management using 802.1X:

(Cisco Controller) >config wlan security wpa akm ft-802.1X enable <WLAN id>

This is how to configure FT authentication management using PSK:

(Cisco Controller) >config wlan security wpa akm ftp-psk enable <WLAN id>

DHCP Required OptionFor enhanced security, Cisco recommends that you require all clients to obtain their IP addresses from a DHCP server.

The DHCP Required option in WLAN settings allows you to force clients to do a DHCP address request/renew every time they associate to the WLAN before they are allowed to send or receive other traffic to the network. From a security standpoint, this allows for a more strict control of IP addresses in use. But also might have an effect in the total time for roaming before traffic is allowed to pass again.

Additionally, this might affect some client implementations that do not do a DHCP renew until the lease time expires. This depends on the client types, for example, Cisco 7921 or 7925 phones might have voice problems while they roam if this option is enabled, as the controller does not allow voice or signaling traffic to pass until the DHCP phase is completed. Another example may include Android and some Linux distributions that only do DHCP renew on half the length of the lease time, not on roaming; this may be a problem if client expires.

Some third-party printer servers might also be affected. In general, it is a good idea not to use this option if the WLAN has non-Windows clients. This is because the more strict controls might induce connectivity issues, based on how the DHCP client side is implemented.

This is how you verify:


WLAN Identifier.................................. 1Profile Name..................................... WLAN-1Network Name (SSID).............................. WLAN-1Status........................................... EnabledMAC Filtering.................................... Disabled…mDNS Status...................................... EnabledmDNS Profile Name................................ default-mdns-profileDHCP Server...................................... DefaultDHCP Address Assignment Required................. Enabled

Rogue ManagementRogue wireless devices are an ongoing threat to corporate wireless networks. Network owners need to do more than just scan for unknown devices: they must be able to detect, disable, locate and manage rogue/intruder threats automatically and in real time.

Rogue Access points can disrupt wireless LAN operations by hijacking legitimate clients and using plain text or other denial-of-service or man-in-the-middle attacks. That is, a hacker can use a rogue Access point to capture sensitive information, such as passwords and usernames. The hacker can then transmit a series of clear-to-send (CTS) frames, which mimics an Access point informing a particular wireless


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LAN client adapter to transmit and instructing all others to wait. This scenario results in legitimate clients being unable to access the wireless LAN resources. Thus, wireless LAN service providers have a strong interest in banning rogue Access points from the air space.


(Cisco Controller) >show rogue ap summary

Rogue Detection Security Level................... customRogue Pending Time............................... 180 secsRogue on wire Auto-Contain....................... DisabledRogue using our SSID Auto-Contain................ DisabledValid client on rogue AP Auto-Contain............ DisabledRogue AP timeout................................. 1200Rogue Detection Report Interval.................. 10Rogue Detection Min Rssi......................... -128Rogue Detection Transient Interval............... 0Rogue Detection Client Num Thershold............. 0Total Rogues(AP+Ad-hoc) supported................ 2000Total Rogues classified.......................... 41

MAC Address Classification # APs # Clients Last Heard ----------------- ------------------ ----- --------- -----------------------00:0d:67:1e:7c:a5 Unclassified 1 0 Thu Feb 6 22:04:38 201400:0d:67:1e:7c:a6 Unclassified 1 0 Thu Feb 6 22:04:38 201400:0d:67:1e:7c:ac Unclassified 2 0 Thu Feb 6 22:04:38 2014

Rogue DetectionThere are good reasons to use rogue detection to minimize security risks, such as in a corporate environment. However, there are certain scenarios in which rogue detection is not needed, for example in OEAP deployment, open venues/stadium, citywide and outdoors. Using outdoor mesh APs to detect rogues would provide little value while incurring resources to analyze. Finally, it is critical to evaluate (or avoid altogether) rogue auto-containment, as there are potential legal issues and liabilities if left to operate automatically.

To verify rogue detection on AP:

(Cisco Controller) >show ap config general <AP Name>

Cisco AP Identifier.............................. 4Cisco AP Name.................................... AP1140Country code..................................... Multiple Countries:PT,USRegulatory Domain allowed by Country............. 802.11bg:-AE 802.11a:-AEAP Country code.................................. US - United StatesAP Regulatory Domain............................. 802.11bg:-A 802.11a:-A ..AP Link Latency.................................. DisabledRogue Detection.................................. Enabled

To enable rogue detection on an AP:

(Cisco Controller) >config rogue detection enable <Cisco AP>


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Min-RSSI

A rogue with a weak RSSI does not provide any valuable information to the network administrator other than it has been heard. A rogue with a weak RSSI also poses less of a threat to the wireless network than a rogue with a stronger signal. Too many weak signaled rogues could clutter the Prime Infrastructure GUI, making rogue mitigation difficult. This can now be avoided by limiting the minimum RSSI value (Minimum RSSI for Rogue Classification) that the AP needs to report the rogue at.

To configure rogue detection based on minimum RSSI of -70dBm:

(Cisco Controller) >config rogue detection min-rssi -70

Configure rogue detection security level to low (no auto-containment):

(Cisco Controller) >config rogue detection security-level low

Rogue Rules

Create a rogue rule for additional conditions set. For example, create ‘rule1’:

(Cisco Controller) >config rogue rule add ap priority 1 classify malicious notify all state alert rule1

Activate the rule:

(Cisco Controller) >config rogue rule enable rule1

To verify rule summary:

(Cisco Controller) >show rogue rule summary

Priority Rule Name Rule state Class Type Notify State Match Hit Count-------- -------------------------------- ----------- ----------- -------- -------- ------ ---------1 rule1 Enabled Malicious All Alert Any 0

Up to 6 conditions can be added to a Rogue Rule.

Adding condition based rules can help to easily detect people spoofing on your network. To configure condition rule based on a managed SSID:

(Cisco Controller) >config rogue rule condition ap set managed-ssid rule1

Add condition based on specific SSID name:

(Cisco Controller) >config rogue rule condition ap set ssid <SSID_name> rule1

Add condition based on minimum RSSI, for example, -70dBm:

(Cisco Controller) >config rogue rule condition ap set rssi -70 rule1

Add condition based on duration (in seconds) the rogue has been detected, for example, 120 seconds:

(Cisco Controller) >config rogue rule condition ap set duration 120 rule1

Confirm rogue rule conditions:

(Cisco Controller) >show rogue rule detailed rule1

Priority......................................... 1Rule Name........................................ rule1State............................................ DisabledType............................................. MaliciousNotify........................................... AllState ........................................... AlertMatch Operation.................................. Any


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Hit Count........................................ 0Total Conditions................................. 3Condition 1 type......................................... Duration value (seconds).............................. 120Condition 2 type......................................... Managed-ssid value........................................ EnabledCondition 3 type......................................... Rssi value (dBm).................................. -70

Wi-Fi Direct

Wi-Fi Direct allows Wi-Fi devices to make direct connections to one another quickly and conveniently like printing, synchronizing, and sharing content. A security concern can arise for the wireless network if the device is connected to both the infrastructure and a Personal Area Network (PAN) at the same time. Cisco recommends to disallow Wi-Fi direct clients to prevent a security hole.

Disallow Wi-Fi direct clients from associating with the WLAN:

(Cisco Controller) >config wlan wifidirect not-allow <WLAN-id>

Channels Scanning for Rogues

For a local/FlexConnect mode/Monitor mode AP there is an option under RRM configuration, which allows the user to choose which channel is scanned for rogues. Depending on the configuration, the AP scans all channel/country channel/DCA channels for rogues. These are the quick explanation on benefits of each:

– For higher security, choose all channel.

– Choose DCA channels for performance, as system will scan as least as possible

– For a balance of performance and security, choose country channel option.

This is an example to configure 5GHz channel scanning for Rogue Detection for all channels:

(Cisco Controller) >config advanced 802.11a monitor channel-list all

This is an example to configure 2.4GHz monitor channel scanning in configured country code:

(Cisco Controller) >config advanced 802.11b monitor channel-list country

Transient Rogue Interval

Using the transient interval values, you can control the time interval at which APs should scan for rogues. APs can also filter rogues based on their transient interval values.

This feature has the following advantages:

– Rogue reports from APs to the controller are shorter.

– Transient rogue entries are avoided in the controller.

– Unnecessary memory allocation for transient rogues is avoided.

Configure transient rogue interval of 2mins (120 seconds):

(Cisco Controller) >config rogue detection monitor-ap transient-rogue-interval 120


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Wireless/RF

Enable Adhoc Rogue DetectionSimilar to general rogue detection, adhoc rogue detection may be ideal in certain scenarios, such as corporate where security is justifiable. However in scenarios such as open venues/stadiums, citywide and public outdoors is not of value.

Enable ad hoc rogue detection and reporting by entering this command:

(Cisco Controller) >config rogue adhoc enable

Enable Rogue Clients AAA ValidationA good reason to enable AAA validation for rogue clients is so that the WLC will reliably and continuously checking for a client to exist on the AAA server, then marking it either valid or malicious.

(Cisco Controller) >config rogue client aaa enable

Enable Rogue Clients MSE ValidationIf there is a Mobility Services Engine (MSE) is available and integrated, it can share information in its learned clients database to compliment the WLC in validating whether a client is valid or a threat.

Enable the use of MSE (if available) to check if rogue clients are valid:

(Cisco Controller) >config rogue client mse enable

Wireless/RFFor any wireless deployment, always do a proper site survey in order to insure proper quality of service for your wireless clients. The requirements for voice or location deployments are stricter than for data services. Auto RF might help on channel and power settings management, but it cannot correct a bad RF design.

The site survey must be done with devices that match the power and propagation behavior of the devices to be used on the real network. For example, do not use an older 802.11b/g radio with omni antenna to study coverage if the final network uses more modern dual radios for 802.11a/b/g with n and 802.11ac data rates.

Disable Low Data RatesYou must carefully plan the process to disable or enable data rates. If your coverage is sufficient, it is often a good idea to incrementally disable lower data rates one by one. Management frames like ACK or beacons will be sent at the lowest mandatory rate (typically 1Mbps), which slows down the whole throughput as the lowest mandatory rate consumes the most airtime.

Try not to have too many supported data rates so that clients can down-shift their rate faster when retransmitting. Typically clients try to send at the fastest data rate they can and if the frame does not make it through, will retransmit at the next lowest data rate and so on until the frame goes through. The removal of some supported rates means that clients who retransmit a frame directly down-shift several data rates, which increases the chance for the frame to go through at the second attempt.

– Beacons are sent at the lowest mandatory rate, defining roughly the cell size.


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Wireless/RF

– Multicast is sent on the range between lowest and highest priority, depending on associated clients.

– If your design does not require low data rates, consider disabling the 802.11b data rates (1, 2 ,5.5 and 11) and leave the rest enabled.

– You might make a conscious decision to not disable all rates below 11Mbps in order to not stop the support of 802.11b-only clients.

The following example serves only as an example as it should not be viewed as solely optimal for every design (do not use as strict guideline). These changes are sensitive and heavily dependent on your RF coverage design.

– For example, if designing for hotspot, have the lowest enabled, because the goal is to have coverage gain versus speed.

– Conversely, if you are designing for a high-speed network, with already good RF coverage, disable the lowest.

Example to disable low data rates (5GHz and 2.4GHz):

(Cisco Controller) >config 802.11a disable network

(Cisco Controller) >config 802.11a 11nSupport enable

(Cisco Controller) >config 802.11a rate disabled 6




(Cisco Controller) >config 802.11a rate mandatory 24

(Cisco Controller) >config 802.11a rate supported 36



(Cisco Controller) >config 802.11a enable network

(Cisco Controller) >config 802.11b disable network

(Cisco Controller) >config 802.11b 11gSupport enable

(Cisco Controller) >config 802.11b 11nSupport enable

(Cisco Controller) >config 802.11b rate disabled 1


(Cisco Controller) >config 802.11b rate disabled 5.5




(Cisco Controller) >config 802.11b rate supported 12


(Cisco Controller) >config 802.11b rate mandatory 24





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Wireless/RF

(Cisco Controller) >config 802.11b enable network

Lower the Number of SSIDsCisco recommends to limit the number of service set identifiers (SSIDs) configured at the controller. You can configure 16 simultaneous SSIDs (per radio on each Access point (AP)), but as each WLAN/SSID needs separate probe responses and beaconing, the RF pollution increases as more SSIDs are added. Furthermore, some smaller wireless stations like PDA, WiFi Phones, and barcode scanners cannot cope with a high number of basic SSID (BSSID) information. This results in lockups, reloads, or association failures. Also the more SSIDs, the more beaconing needed, so less RF time is available for real data transmits. For example, the recommendation is to have 1 to 3 SSIDs for corporate, and 1 SSID for high-density designs. AAA override can be leveraged for per user VLAN/ settings on a single SSID scenario.

Enter this command in order to verify:

(Cisco Controller) >show wlan summary

Number of WLANs.................................. 8

WLAN ID WLAN Profile Name / SSID Status Interface Name------- ------------------------------------- -------- --------------------1 WLAN-Local / WLAN-Local Enabled management 2 WLAN-Lync / WLAN-Lync Enabled Lync3 WLAN-AVC / WLAN-AVC Enabled AVC4 WLAN-11ac / WLAN-11ac Enabled 11ac 5 WLAN-Visitor / WLAN-Visitor Enabled Visitor 6 WLAN-1X / WLAN-1X Enabled 1X 7 WLAN-23 / WLAN-23 Enabled 23 8 WLAN-HS2 / WLAN-HS2 Enabled HS2

Disable unnecessary SSIDs:

(Cisco Controller) >config wlan disable 8




…


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Wireless/RF

Enable Band SelectionBand selection enables client radios that are capable of dual-band (2.4- and 5-GHz) operation to move to a less congested 5-GHz Access point. The 2.4-GHz band is often congested. Clients on this band typically experience interference from Bluetooth devices, microwave ovens, and cordless phones as well as co-channel interference from other Access points because of the 802.11b/g limit of three non-overlapping channels. To prevent these sources of interference and improve overall network performance, you can configure band selection on controller

– Band selection is enabled/disabled globally by default.

– Band selection works by regulating probe responses to clients. It makes 5-GHz channels more attractive to clients by delaying probe responses to clients on 2.4-GHz channels.

– Do not use band selection for voice, as it can slow down roaming.

– Some client types do not work well with band selection enabled.

– Most new clients prefer 5GHz by default.

– Do not use band selection on high-density designs.

Enter this command in order to verify:

(Cisco Controller) >show band-select

Band Select Probe Response....................... per WLAN enabling Cycle Count................................... 2 cycles Cycle Threshold............................... 200 milliseconds Age Out Suppression........................... 20 seconds Age Out Dual Band............................. 60 seconds Client RSSI................................... -80 dBm

Enable or disable band selection on specific WLANs:

(Cisco Controller) >config wlan band-select allow enable <WLAN id>

DCA – Dynamic Channel Assignment

When a wireless network is first initialized, all radios participating require a channel assignment in order to operate without interference – optimizing the channel assignments to allow for interference free operation is DCA’s job. Wireless network does this using the air metrics reported by each radio on every possible channel, and providing a solution that maximizes channel bandwidth and minimizes RF interference from all sources – Self (signal), other networks (foreign interference), Noise (everything else).

DCA is enabled by default and provides a global solution to channel planning for your network.

• Let RRM automatically configure all 802.11a or 802.11b/g channels based on availability and interference:

(Cisco Controller) >config 802.11a channel global auto

(Cisco Controller) >config 802.11b channel global auto

Channel Widths

802.11n can operate in a 40 MHz channel by bonding two 20 MHz channels together and this significantly increases throughput. Not all 802.11n devices support 40 MHz bonded channels (clients). 802.11ac allows for bonding of 20 MHz channels into an 80 MHz wide channel for 802.11ac usage, and


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Wireless/RF

all Clients must support 80 MHz. This is not practical for 2.4 GHz as there are a very limited number of non overlapping 20 MHz channels available. However, in 5 GHz this can represent a significant increase in throughput and speed provided you have enough 20 MHz channels (see DFS below).

Use this command to set DCA assigned channel width to all capable radios.

(Cisco Controller) config advanced 802.11a channel dca chan-width-11n <20 | 40 |80>

Enter this command to configure the channel width for a particular Access point to 40MHz or 80 MHz:

(Cisco Controller) >config 802.11a chan_width <Cisco AP> 40/80

Channel width overview:

– 20 permits the radio to communicate using only 20-MHz channels. Choose this option for legacy 802.11a radios, 20-MHz 802.11n radios, or 40-MHz 802.11n radios that you want to operate using only 20-MHz channels. This is the default value.

– 40 permits 40-MHz 802.11n radios to communicate using two adjacent 20-MHz channels bonded together. The radio uses the primary channel that you choose as the anchor channel (for beacons) as well as its extension channel for faster data throughput. Each channel has only one extension channel (36 and 40 are a pair, 44 and 48 are a pair, and so on). For example, if you choose a primary channel of 44, the Cisco WLC would use channel 48 as the extension channel. If you choose a primary channel of 48, the Cisco WLC would use channel 44 as the extension channel.

Note This parameter can be configured only if the primary channel is statically assigned

– 80 sets the channel width for the 802.11ac radios to 80 MHz.

Note Statically configuring an Access point’s radio for 20-MHz, 40-MHz or 80-MHz mode overrides the globally configured DCA channel width setting configured using the config advanced 802.11a channel dca chan-width-11n {20 | 40 |80} command. If you ever change the static configuration back to global on the Access point radio, the global DCA configuration overrides the channel width configuration that the Access point was previously using. Change takes effect within 30 minutes depending on how often DCA is configured to run.

Note Channels116,120,124,and128arenotavailableintheU.S.andCanadafor40‐MHzchannelbonding

20-MHz

20-MHz

Gained Space

11a/n/ac/ 20 MHz

11a/n/ac/ 40 MHz 11a/n/ac/ 80 MHz

3525

05

40-MHz

40-MHz

80-MHzGained Space


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Wireless/RF

DFS – Dynamic Frequency Selection

Not all channels are created at once. Dynamic Frequency Selection was created to increase the availability of more channels in the 5 GHz spectrum. Depending on regulatory domain this can mean from 4 to 12 additional channels. More channels implies more capacity.

DFS detects radar signals and ensures that there is no interference with weather radar that may be operating on our frequency. The DFS specification also designates the Master (our AP) as the monitor for the group that will steer clients and the AP away from any signals that are detected. Traditionally there has been some misgivings in North America about using DFS channels – but then we have 8 that are not DFS. In the ETSI regulatory domain (Europe) – they have 4 non DFS channels and have been using DFS channels successfully for many years.

Although the 5GHz band offers more channels, care should be given in the overall design as the 5GHz channels have varying power and indoor/outdoor deployment restrictions. For example, in North America, the U-NII-1 can only be used indoors and it has power restriction of 50mW maximum power, both U-NII-2 & U-NII-2e are subject to Dynamic Frequency Selection).

• By default U-NII-2e channels are disabled in the DCA channel list. Check what channels are being used using this command.

(Cisco Controller) show>advanced 802.11a channel

<snip>

802.11a 5 GHz Auto-RF Channel List

Allowed Channel List..36,40,44,48,52,56,60,64,149,153,157,161

Unused Channel List..100,104,108,112,116,120,124,128,132,136,140,165

DCA Outdoor AP option.......................... Disabled

– Enable the U-NII-2e channels for more channels in your regulatory domain using this command.

(Cisco Controller) >config advanced 802.11a channel add <channel>

Available channels in North America and Europe are 100-140 (8 additional channels). Channels 120, 124, 128 are disabled in the US, and severely penalized in ETSI DFS rules and are not supported.

Frequency in MHz

UNII - 2 Extended BandUNII - 2 Band

UNII - 1 Band

5180

5200

5220

5240

5260

5250

5350

5470

5280

5300

5320

5500

5520

5540

5560

5580

5600

5620

5640

5660

5680

5700 35

2506


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Application Visibility and Control (AVC)

DCA Restart

Once you have made selections for channels and channel widths,or in the case of a new network completed installing all APs, DCA will manage the channels dynamically and make adjustments as needed over time and changing conditions. However if this is a new installation, or you have made major changes to DCA such as changing channel widths or adding new APs, then you can restart the DCA process which initializes an aggressive search mode (startup), and provides an optimized starting channel plan.

In order to determine which WLC is currently the group leader run this command –

(Cisco Controller) >show advanced 802.11a group

(Cisco Controller) >show advanced 802.11b group

From the identified group leader re-initialize DCA by running this command

(Cisco Controller) >config advanced 802.11a channel global restart

(Cisco Controller) >config advanced 802.11b channel global restart

Verify the restart by running this command -

(Cisco Controller) >show advanced 802.11a channel

<snip>

Last Run Time.................................. 0 seconds DCA Sensitivity Level.......................... STARTUP (5 dB) DCA 802.11n/ac Channel Width................... 80 MHz DCA Minimum Energy Limit....................... -95 dBm

If successful you will see DCA sensitivity showing the STARTUP banner.

Note Startup mode will run for 100 minutes – reaching a solution generally within 30-40 minutes. This can be disruptive to clients (lots of channel changes) if you have made significant changes (channel width, numbers of AP’s). Do this step last – as changes during the startup change the question you are asking.

Application Visibility and Control (AVC)Application Visibility and Control (AVC) classifies applications using Cisco's Deep Packet Inspection (DPI) techniques with Network-Based Application Recognition (NBAR) engine and provides application-level visibility and control into Wi-Fi network. After recognizing the applications, the AVC feature allows you to either drop or mark the traffic.

Using AVC, the controller can detect more than 1000 applications. AVC enables you to perform real-time analysis and create policies to reduce network congestion, costly network link usage, and infrastructure upgrades.

AVC is supported on the following controller platforms: Cisco 2500 Series Controllers, Cisco 5500 Series Controllers, Cisco Flex 7500 Series Controllers in central switching mode, Cisco 8500 Series Controllers, and Cisco WiSM2.

To enable AVC visibility on a WLAN (for baseline application utilization):

(Cisco Controller) >config wlan avc 1 visibility enable

To show AVC statistics on a WLAN (show application utilization per WLAN):

(Cisco Controller) >show avc statistics wlan <WLAN id>


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Enable 802.11k for Optimal Roaming

A general use-case is to mark/drop/rate-limit traffic, such as in this example to prioritize Microsoft Lync traffic for best user experience when making a Lync video/voice call.

To create the AVC profile:

(Cisco Controller) >config avc profile MSLync create

To add one or more rules to the AVC profile (mark Lync Audio with DSCP 46, video with DSCP 34):

(Cisco Controller) >config avc profile MSLync rule add application ms-lync-audio mark 46

(Cisco Controller) >config avc profile MSLync rule add application ms-lync-video mark 34

To apply the AVC profile to a WLAN:

(Cisco Controller) >config wlan avc <WLAN id> profile MSLync

Here is an example to drop Youtube:

(Cisco Controller) >config avc profile DropYoutube rule add application youtube drop

Show AVC profile summary:

(Cisco Controller) >show avc profile summary

Profile-Name Number of Rules============ ============== AVC-Profile-1 3 AVC-Profile-2 0 drop-jabber-video 1 MSLync 2 To show the AVC profile detail:

(Cisco Controller) >show avc profile detailed MSLync

Application-Name Application-Group-Name Action DSCPDIR AVG-RATELIMIT BURST-RATELIMIT ================ ======================= ====== ==== ===== ============= ============= ms-lync-audio business-and-productivity-tools Mark 46 Bidirectional ms-lync-video business-and-productivity-tools Mark 34 Bidirectional

Associated WLAN IDs : 1 Associated Remote LAN IDs : Associated Guest LAN IDs :

Enable 802.11k for Optimal RoamingThe 802.11k standard allows clients to request neighbor reports containing information about known neighbor Access points that are candidates for a service set transition. The use of the 802.11k neighbor list can limit the need for active and passive scanning.

A common problem 802.11k help to solve is to deal with “sticky clients”, those that seem to associate with a specific AP, and then hold onto that connection so stubbornly even when there are significantly better options available from nearer Access points.

Enable 802.11k neighbor list for a WLAN:

(Cisco Controller) >config wlan assisted-roaming neighbor-list enable <WLAN id>

Enable dual-band 802.11k neighbor list for a WLAN by entering this command:


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Mobility

(Cisco Controller) >config wlan assisted-roaming dual-list enable <WLAN id>

Enable assisted roaming prediction list feature for a WLAN:

(Cisco Controller) >config wlan assisted-roaming prediction enable <WLAN id>

MobilityThese are the best practices for mobility:

• All controllers in a mobility group should have the same IP address for a virtual interface, for example 192.0.2.x. This is important for roaming. If all the controllers within a mobility group do not use the same virtual interface, inter-controller roaming can appear to work, but the hand-off does not complete and the client loses connectivity for a period of time.


(Cisco Controller) >show interface summary

Interface Name Port Vlan Id IP Address Type Ap Mgr----------------- ----- -------- --------------- ------- ------ap-manager LAG 15 192.168.15.66 Static Yes management LAG 15 192.168.15.65 Static No service-port N/A N/A 10.48.76.65 Static No test LAG 50 192.168.50.65 Dynamic No virtual N/A N/A 192.0.2.1 Static No

• The virtual gateway address must be not routable inside your network infrastructure. It is only intended to be reachable for a wireless client when connected to a controller, never from a wired connection.

• IP connectivity must exist between the management interfaces of all controllers.

• In most situations, all controllers must be configured with the same mobility group name. Exceptions to this rule are deployments on controllers for the Guest Access feature, typically in a Demilitarized Zone (DMZ).

• The group name is used as a PMK/L2 fast roaming discriminator; for fast roaming design it is required to have the same group name.

• When deploying for webauth/guest, it is not required to have the same mobility group name.

• It is a safe trick to run all WLCs on the same software code versions to ensure you do not face inconsistent behaviors due to bugs present on some WLCs and not others. For software Release 6.0 and later, all versions are inter-compatible for mobility purposes so it is not mandatory.

• Do not create unnecessarily large mobility groups. A mobility group should only have all controllers that have Access points in the area where a client can physically roam, for example all controllers with Access points in a building. If you have a scenario where several buildings are separated, they should be broken into several mobility groups. This saves memory and CPU, as controllers do not need to keep large lists of valid clients, rogues and Access points inside the group, which would not interact anyway.

• Also, try to accommodate the AP distribution across controllers in the mobility group so that there are APs. For example, per floor or per controller, and not a salt and pepper distribution. This reduces inter-controller roaming, which has less impact on the mobility group activity.

• In scenarios where there is more than one controller in a mobility group, it is normal to see some rogue Access point alerts about our own Access points in the network after a controller reload. This happens due to the time it takes to update the Access point, client and rogue lists between mobility group members.


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Mobility

Configure Mobility Multicast ModeConfiguring multicast mode for mobility allows the client to announce messages to be sent on multicast between mobility peers, instead of unicast sent to each controller, with benefits on time, CPU usage, and network utilization.

Note Make sure multicast traffic is passing between controllers when their management is on different subnets.


(Cisco Controller) >show mobility summary

Mobility Protocol Port........................... 16666Default Mobility Domain.......................... rfdemoMulticast Mode .................................. EnabledMobility Domain ID for 802.11r................... 0x6569Mobility Keepalive Interval...................... 10Mobility Keepalive Count......................... 3Mobility Group Members Configured................ 2Mobility Control Message DSCP Value.............. 0

Controllers configured in the Mobility GroupMAC AddressIP Address Group NameMulticast IP Statusd0:c2:82:dd:66:a0 10.10.10.5 rfdemo 239.0.2.1 Up


(Cisco Controller) >config mobility multicast-mode enable <local-multicast-address, e.g. 239.0.2.1>


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Enable Fast SSID Changing

Enable Fast SSID ChangingWhenfastSSIDchangingisenabled,the controller allowsclientstomovefasterbetweenSSIDs.WhenfastSSIDisenabled,thecliententryisnotclearedandthedelayisnotenforced.ThisisveryimportanttohaveforsupportingAppleIOSdevices.

To enable fast SSID change:

(Cisco Controller) >config network fast-ssid-change enable

Enable CleanAirTo effectively detect and mitigate RF interference, enable CleanAir whenever possible. There are recommendations to various sources of interference to trigger security alerts, such as generic DECT phones, jammer, and so on.

To verify CleanAir configuration on the network (802.11b):

(Cisco Controller) >show 802.11b cleanair config

To verify CleanAir configuration on the network (802.11a):

(Cisco Controller) >show 802.11a cleanair config

Clean Air Solution............................... DisabledAir Quality Settings: Air Quality Reporting........................ Enabled Air Quality Reporting Period (min)........... 15 Air Quality Alarms........................... Enabled Air Quality Alarm Threshold................ 35 Unclassified Interference.................. Disabled Unclassified Severity Threshold............ 20Interference Device Settings: Interference Device Reporting................ Enabled Interference Device Types: Bluetooth Link........................... Enabled Microwave Oven........................... Enabled 802.11 FH................................ Enabled Bluetooth Discovery...................... Enabled TDD Transmitter.......................... Enabled

To enable CleanAir functionality on the 802.11 network:

(Cisco Controller) >config 802.11b cleanair enable network

(Cisco Controller) >config 802.11a cleanair enable network

Configure to enable interference detection for specifically jammer, for example:

(Cisco Controller) >config 802.11b cleanair device enable jammer

To verify CleanAir is enabled on 802.11 network:

(Cisco Controller) >show 802.11a cleanair config

(Cisco Controller) >show 802.11b cleanair config

Clean Air Solution............................... EnabledAir Quality Settings: Air Quality Reporting........................ Enabled Air Quality Reporting Period (min)........... 15 Air Quality Alarms........................... Enabled Air Quality Alarm Threshold................ 35


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Enable High Availability Client/AP SSO

Unclassified Interference.................. Disabled Unclassified Severity Threshold............ 20Interference Device Settings: Interference Device Reporting................ Enabled Interference Device Types: TDD Transmitter.......................... Enabled Jammer................................... Enabled Continuous Transmitter................... Enabled DECT-like Phone.......................... Enabled Video Camera............................. Enabled


AP Stateful switchover (AP SSO)High Availability (HA) feature APSSO set within the Cisco Wireless LAN Controller (WLC) network software release version 7.3 and 7.4 allows the Access point (AP) to establish a CAPWAP tunnel with the Active WLC, and share a mirror copy of the AP database with the Standby WLC. The APs do not go into the Discovery state when the Active WLC fails, and the Standby WLC takes over the network as the Active WLC. There is only one CAPWAP tunnel maintained at a time between the APs and the WLC that is in an Active state. The overall goal for the addition of AP SSO support to the Cisco Wireless LAN Controller Network is to reduce major downtime in wireless networks due to failure conditions that may occur due to box fail over or network fail over.

To support High Availability without impacting service, there needs to be support for seamless transition of clients and APs from the active controller to the standby controller. Release 7.5 supports Client Stateful Switch Over (Client SSO) in Wireless LAN controllers. Client SSO will be supported for clients which have already completed the authentication and DHCP phase, and have started passing traffic. With Client SSO, a client information is synced to the Standby WLC when the client associates to the WLC, or when the client parameters change. Fully authenticated clients, the clients in Run state, are synced to the Standby. Thus, client re-association is avoided on switchover making the fail over seamless for the APs as well as for the clients, resulting in zero client service downtime and no SSID outage.

Note Please refer to the Cisco Wireless LAN Controller Configuration Guide for more details.


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http://www.cisco.com/c/en/us/td/docs/wireless/controller/7-6/configuration/guide/b_cg76/b_cg76_chapter_01101111.html


Before You Begin HA Configuration

Ensure that the management interfaces of both controllers are in the same subnet.

Configure a local redundancy IP address and a peer redundancy management IP address by entering this command:

(Cisco Controller) > config interface address redundancy-management ip-addr1 peer-redundancy-management ip-addr2

Configure the role of a controller by entering this command:

(Cisco Controller) > config redundancy unit {primary | secondary}

Configure the redundancy mode for SSO by entering this command:

(Cisco Controller) > config redundancy mode sso

Both controllers now reboot and then negotiate the roles of active and standby-hot controllers.

Configure the route configurations of the standby controller by entering this command:

(Cisco Controller) > config redundancy peer-route {add network-ip-addr ip-mask | delete network-ip-addr}

This command can be run only if the HA peer controller is available and operational.

Configure the IP address and netmask of the peer service port of the standby controller by entering this command:

(Cisco Controller) > config redundancy interface address peer-service-port ip-address netmask

This command can be run only if the HA peer controller is available and operational.

Initiate a manual switchover by entering this command:

(Cisco Controller) > config redundancy force-switchover

Run this command only when you require a manual switchover.

Configure the redundancy timers by entering this command:

(Cisco Controller) > config redundancy timer {keep-alive-timer time-in-milliseconds | peer-search-timer time-in-seconds}

Configure encryption of communication between controllers by entering this command:

(Cisco Controller) > config redundancy link-encryption {enable | disable}


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Technology

Cisco wireless lan controller configuration best practices